The invention relates to a laterally releasable jaw unit, in particular to the toe unit of a safety ski binding and has particular reference to a ski binding which also has a jaw which holds the other end of the ski boot, in particular a heel jaw which preferably also exerts a resilient thrust force in the longitudinal direction of the ski on the laterally releasable jaw unit via the ski boot.
One known form of toe unit comprises a binding housing, a sole clamp having two lateral limbs and a hold-down clamp disposed on the housing adjacent the ski boot and a release spring disposed in the binding housing substantially in the longitudinal direction of the ski. The release spring acts at one end on the binding housing and exerts via its other end a force on the sole clamp, the force having a substantial component in the longitudinal direction of the ski and in the direction away from the ski boot. Tilting surfaces are arranged at the side of the binding housing facing the ski boot on both sides of the vertical central longitudinal plane, with the tilting surfaces having mutually parallel, straight tilting axes standing substantially upright from the surface of the ski. Complementary tilting counter-surfaces provided on the side of the sole clamp facing away from the ski boot act on the tilting surfaces under the action of the release force in such a way that with excessive lateral forces on the ski boot the sole clamp pivots outwardly against the force of the release spring and releases the ski boot.
A releasable toe unit for ski bindings is already known (AT-PS 300 630) in which a sole hold-down clamp is arranged on a laterally releasable toe unit, with the sole hold-down clamp being able to deviate resiliently upwardly against the bias of a spring. This is intended to prevent the boot exerting abnormal loads on the binding and on the ski, and thus changing the functional characteristics of the binding, for example when a layer of snow is present between the boot and the ski. The disadvantage of this known ski binding is the requirement for a special hold-down spring.
It is also already known (DE-OS 32 30 186) to derive the resilient hold-down force acting on the sole hold-down clamp from the release spring extending in the longitudinal direction of the ski. However, for this it is necessary to allow the one end of the release spring to act on the sole hold-down clamp and for the other end of the release spring to act on the sideways release mechanism. For this purpose the front end of the release spring must also be movable together with the components which support it and this is a disadvantage both from the point of view of the construction and also of the operation.
In accordance with an older proposal (DE-OS 36 05 313) provision is made for the sole hold-down clamp, the side jaws, the sideways release mechanism and the point of action of the release spring on the sideways release mechanism to be arranged on a carrier part which is pivotable upwardly relative to the binding housing about a transverse axle. The transverse axle is located at a distance above the line of action of the release spring such that a predetermined, resiliently yielding hold-down force originating from the release spring acts from the top side on the sole of the ski boot. In this way a torque is generated by the release spring about the transverse axle which tries to move the sole hold-down clamp downwardly. As a result of this construction one avoids not only the disadvantages brought by a layer of snow between the sole of the boot and the ski, in particular a jamming of the shoe sole, but it is also possible to achieve a restricted degree of friction compensation. If the skier should enter into a rearward position then the friction on the sole hold-down clamp admittedly increases somewhat, however the friction at the sole plate simultaneously reduces significantly so that the sideways release is not made more difficult, but if anything is made easier, which is entirely desirable in the event of a rearward fall. A disadvantage of this previously known safety ski binding lies in the fact that it is necessary to provide a housing which is pivotable about a transverse axle which brings increased manufacturing complexity and expense.
The principal object underlying the invention is thus to so further develop a laterally releasable jaw unit with a sole clamp which is pivotally laterally about tilting axes, for example as is known from DE-PS 31 29 536, so that with hardly any increase in construction or complexity one automatically prevents the sole of the ski boot from becoming jammed too hard between the hold-down clamp of the sole clamp and the ski surface, or a footplate arranged thereon, and so that in the rear position of the skier the sideways release process is made somewhat easier.